Inserting data with visibilities

Visibilities are boolean AND (&) and OR (|) combinations of authorization
tokens. Authorization tokens are arbitrary strings taken from a restricted
ASCII character set. Parentheses are required to specify order of operations
in visibilities.

Scanning with authorizations

Authorizations are sets of authorization tokens. Each Accumulo user has
authorizations and each Accumulo scan has authorizations. Scan authorizations
are only allowed to be a subset of the user’s authorizations. By default, a
user’s authorizations set is empty.